Improvement in apparatus for casting ordnance



UNITED STaTEs PATENT OEEICEo JAMES MILLHOLLAND, OF READING, PENNSYLVANIA.

IMPROVEMENT IN APPARATUS FOR CASTENG ORDNANCE.

Specification forming part of Letters Patent No. :1L-Lt. lated July 15, 1h62.

.T0 @ZZ whom t may concern:

Be it known that I, JAMEs MILLHOLLAND, of Reading, Berks county, Pennsylvania, have invented Improvementsin Apparatus for Oasting Ordnance; and I do hereby declare the t'ollowing to be a full, clear, and exact description ot' the same, reference-being had to the accompanying drawings, and to the letters of reference marked thereon.

My invention relates to improve1nents,fully described hereinaftenin apparatus appertaining to revolving molds for casting ordnance and other like lengthy objects.

In order to enable others skilled in the art to practice my inventiou,.lwill now proceed to describe the manner of carrying it into eil'ect.

On reference to the accompanying drawi ugs, which form apart of this specitication, Figure l is a vertical section of my improved apparatus for casting ordnance, rolls,v and other like lengthy objects. Fig. 2 isa plan View.

A is a hollow cylinder, ruade ot' cast-iron or of substantial plate-iron, closed at the bottom and open at the top, where it is provided with a flange, a. To the latter is secured a crosspiece, made of the two parts Band B, theiorm of which will be best observed on reference to Fig. 2, the two parts being secured to each other by bolts b b passing through lugs c c. This cross-pieee is so constructed as to present a central opening, which serves as the bearing for the hub oi' the bevel-wheel C, the'latter being provided with a colla-r, c, which lits into a recess of corresponding` size cnt in the crosspieces, so that although the bevel-wheel C is capable of rotating freely in its bearings in the cross-piece, it is prevented by the collar c from moving vertically. In the inside ofthe hub'otl the wheel O are cut four or any other convenient number of vertical slots or recesses for the reception of a like number'of vertical keys or feathers on the upper end of the tapering tube D, so that while the latter revolves with the wheel it can have a limited vertical movement. The lower end of the tube D is provided with a lange, al, which is secured to a similar flange, f, on thehollow base E,which `l'orms a continuation of the said tube D, the lower end of the hollow base having a flange, m, secured to a plate, j, from the under side of which projects a journal, 71 adapted to a step, i', secured to the bottom of the cylindrical casing A.

Into the wheel C gears a pinion, G, on a shaft, H, which turns in a projection,'I, se cured to or forming a part of the cylindrical tube A, the shaft bein g furnished with a pulley for receiving a strap or being driven by any suitable system of gearing.

ln forming the molds the pattern,which is of a form to correspondtothat of the exterior ofthe cannon to be cast, is suspended within the chamber formed by the tube D and its base E. The space intervening between the pattern and the sides and bottom otl the chamber is then rammed tightly with molding-sand, the usual channel for pouring in the metal from the top being formed in the mold. After this the pieces B and B forming the cross-bar are detached from the Hange a on the top of the cylinder A, and are disconnected from each other, thereby setting the bevel-wheel C at liberty, and allowing the mold, consisting of the tube D, its detachable base, the packed sand and the iuclosed pattern, to be elevated from the cylinder A and placed in a proper position for extracting the pattern, which is divided into two parts at a point opposite to the line x. The bolts which connect the tube D to the hollow base E are withdrawn, and the latter,coutaining the lower portion of the pattern, separated from the former, the sand in the base parting from that in the tube at the point 50 where the usual preparation has been made for effecting this separation. The upper portion oi' the pattern is removed fromthe mold longitudinally, the taper of the pattern readily permitting this withdrawl, while the,

hollow base with 'the lower portion of the paty tern is inverted, the platej removed, and the ramrning of the sand iu this portion of the mold completed priorto the withdrawal of the pattern. After the two parts of themoldhave been properly dried and otherwise treated, as usual, they are again secured to each other, aud the whole replaced in a vertical position within the cylinder A, the journal li fitting in the step 'i'. The two portionsB and B of the crossbar are theu adjusted so as to inclose the hub of the wheel C and its collar e, when the mold is ready to receive the molteniron,which is poured in at the top.- During the pouring in of the metal and afterward, until it becomes nearly rigid, or, aseit is technically termed, Set, a rapid rotary motion is imparted to the shaft H, and consequently to the mold and its molten contents, and this rotary motion causes the earthy and other light particles to seek the center of the mold,While the heavier metal and the purest portion of the iron seeks the sides of the mold H. The center of the casting being subsequently removed during,` the process of boring', none but the purest and strongest iron remains to resist the shocks to which the cannon is subjected. The rotary motion,too,has the effect of partially paddling the iron and rendering it of thattongh quality so much to be desired in the manufacture ot" ordnance. After the casting has become sut ticiently cool itis Withdrawn, together with the mold, from the cylinder A, thetwo portions of the mold separated, the casting and sand re moved, when the tube and its base are again connected together, ready to` be used in the formation of another mold. It Will be understood that the tube D, as well as its base, are perforated with a number of holes for admitting the rods, by means of which the usual vent`holes for the escape of the gas during the process of casting` are formed. The heat imparted to the tube audits base when the molten metal is poured int-o the mold causes both to expand, and consequently the upper end of the tube D willrise and project through the hub of the wheel C. As the wheel, however, is provided with slots to receive the keys or feathers on the end of the tube, the latter can move freely through the hub of' the Wheel without interfering with the motion ot' either Wheel or tube. The heat would have an injurious effect on the journal 71l and step t but for the presence of a supply of water or other suitable fluid in the bottom ofthe cylinder A, the latter being made fluid-tight, and of safticient diameter to admit a man freely when the cleansing of the interior of the cylinder renders such a proceeding necessary. l

Although I have described my invention as applied to the forming of molds for casting cannon, it will be evident that molds for easting rolls and other like lengthy objects may be made with facility, in the manner above explained.

I wish it to be understood that I do not claim, broadly, imparting a rotary motion to a mold during the process of casting in order that the exterior of the article east may be of the purest iron; but

I claim as my invention anddesire to secure by Letters Patentf l. So constructing` the upper end of the tube D in respect to the gearing` for driving the same that the said tube can expand and eontract Without any interruption of its rotary movement.

2. Combining` the aforesaid tube D and its hollow base with the Water-tight casing A, substantially as and for the purpose herein set forth.

In testimony whereof I have si Le'ned my name to this specification inthe presence of two subscribing witnesses.

JAMES MILLHOLLAND. Witnesses:

HENRY HoWsoN,

JAMES A. MILLHQLLAND. 

